California’s water conservation habits, refined and improved over five years of drought, are quickly evaporating.

For the seventh time in the last eight months, the amount of water saved by urban Californians has declined, according to new data from the State Water Resources Control Board. In other words, lawn sprinklers are back on, showers are getting longer and overall, California’s water use, after five years of conserving, is now back to where it was before the drought began.

“You don’t want to jump to a conclusion and say the sky is falling, everybody has forgotten how to conserve,” said Felicia Marcus, chairwoman of the water board. “But having been through what we’ve been through, we obviously want people to stay aware and redouble our efforts.”

Overall, urban residents reduced the amount of water they use by just .8 percent in January, a far cry from the whopping 20.7 percent reduction in January 2017, compared to January 2013, the baseline year the state uses.

Marcus attributed January’s meager conservation totals to hot, dry weather around the state that month, particularly in Southern California, where temperatures hit the 80s on multiple days, prompting people to turn on lawn sprinklers, which account for half of all urban water use in the state.

Second, after last winter’s relentless storms and floods, with Gov. Jerry Brown declaring the drought emergency over in April, media coverage of water conservation fell, she noted. And finally, cities, water districts and private water companies in many cases removed water conservation advertising and rules — like limits on the number of days landscaping could be watered — that had been in place during the 2012-2017 drought.

A big reason for the heavier use now is that Southern Californians cranked open the faucets this winter.

While residents of the nine Bay Area counties continued their conservation habits — cutting water use 6.9 percent in January, compared with January 2013, the South Coast area, which includes Los Angeles, Riverside, Orange County and San Diego, did the opposite: Residents there used 3.8 percent more water in January than five years ago.

Los Angeles topped them all, using 15.2 percent more compared with five years ago, while Bakersfield saw an increase of 13.5 percent, Riverside 3.1 percent and San Diego 1.4 percent.

By comparison, most big Bay Area cities used less. San Francisco cut water use 12.2 percent over the same period, San Jose Water Company customers cut 9.6 percent, East Bay Municipal Utility District customers cut by 5.3 percent, and Santa Cruz cut by 15.7 percent. But Contra Costa Water District customers — located in hotter inland areas — increased use by 3.9 percent.

The overall statewide trend is making some people nervous. Despite rain and snow last week and more in the forecast for next week, much of this winter has been dry. The Sierra snow pack, which supplies nearly one-third of the water for farms and cities in California, on Thursday was just 38 percent of normal.

Still, most reservoirs are looking good, at average levels or near full, due to the very wet winter last year. But rainfall totals around the state since Oct. 1 are barely half of average in Northern California this winter and about a quarter of average in Southern California.

“People did a fantastic job of conserving water and using it more efficiently during the drought,” said Tracy Quinn, California director of water efficiency for the Natural Resources Defense Council, an environmental group. “We expected some rebound, particularly from people who had stopped watering their lawns, but certainly not to this extent.”

“It’s exacerbated by some water suppliers saying they have plenty of water and there’s no need to conserve,” she added. “They need to sell water to recover their fixed costs, so there is going to be a conflict of interest in really driving conservation.”

Hayward showed the biggest jump in water use of any Bay Area city, up 32.5 percent. That’s in part because of a major water main break in the city in January and because the period it computed its numbers was 35 days long this year, compared with a 30-day period in 2013, said city spokesman Chuck Finnie.

Currently, 47 percent of California is still classified as being in some form of drought, according to the U.S. Drought Monitor, a report put out each week by federal scientists. All of the affected area is south of the Bay Area. The reason: Last winter’s storms didn’t help Southern California as much as Northern California.

The upcoming storms will help the state’s summer outlook. But the typical winter rain season ends April 1, just three weeks from now.

“Generally one dry year doesn’t make a drought,” Marcus said. “But if we don’t get more snow this winter, the reservoirs are going to drop like a rock when the growing season starts and it’s going to be tight.”

Last month, the water board began a process to make permanent the emergency water-wasting regulations that it passed during the drought. Those include bans on hosing down sidewalks, prohibitions against lawn irrigation right after rain and requirements that hotels post signs telling guests they can choose not to have towels and sheets washed every day. Those rules were delayed by a minor legal change and are expected to be voted on in April, Marcus said.

“You’ve got to always assume not that the next year is going to be dry,” she said, “but that the next five years might be dry.”

Paul Rogers has covered a wide range of issues for The Mercury News since 1989, including water, oceans, energy, logging, parks, endangered species, toxics and climate change. He also works as managing editor of the Science team at KQED, the PBS and NPR station in San Francisco, and has taught science writing at UC Berkeley and UC Santa Cruz.

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